Linux – Why ACPI Namespace keeps changing

acpilinux

Does anyone know why the ACPI namespace keeps changing? I had a script a while back on a Red Hat system which read the CPU temperature from '/proc/acpi/thermal_zone/THRM'. Now I have a new (but similar hardware) and relatively same distro (except for a few drivers here and there) and it has changed to '/proc/acpi/thermal_zone/TZ00' and '/proc/acpi/thermal_zone/TZ01'?

Is this even the CPU thermal? Or is it for something else?

I know most will say, read the ACPI docs… But that's beyond the point. Why and who keeps changing the namespace?

Best Answer

ACPI is tied to the hardware which has changed dramatically in the last 15 years. Dual core processors which never existed (or where extremely expensive in '97) are now standard. Modern GPUs are now so power hungry that they may need their own thermal monitors. The cost of adding thermal monitors is now cheap enough other devices may also have thermal monitors.

Don't blame the software people for having to keep up with hardware changes. This is natural. Change can be frustrating. Relax, take ten deep breaths, and adapt if necessary.

Most releases now have a variety of tools to monitor and report temperatures. Many are good at self configuring. You might want to check them out.

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